Mechanical roasting-furnace.



UNITED STATES PATENT OFFIOE.

ROMAN VON ZELEWSKI, OF ENGIS, BELGIUM.

MECHANICAL ROASTING-FURNACE.

Application filed September 11, 1907.

To all whom it may concern:

Be it known that I, ROMAN voN ZnLEwsKI, residing at Engis, in the Kingdom of Belgium, have invented certain new and useful Improvements in Mechanical Roasting- Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

It is a well known fact that the greater number of the existing mechanical roastingfurnaces are continuously worked, i. e. the charging and the discharging of the ores take place without interruptions worth mentioning. The ores leave the discharge openings no matter whether they have been thoroughly roasted or not. It is also known, that ores of the same kind, as for instance zinc-blende, behave differently even if they contain the same percentage of sulfur, or in other words, can be roasted with more or less difficulty only, so that an uninterruptedly worked mechanical roasting-furnace will possess the most suitable structure for a certain kind of ore only, whereas for other kinds of ores it will show unsuitable dimensions and arrangements.

The object of my present invention now is to provide a mechanical roasting-furnace which shall be equipped with two devices arranged independently of each other for stirring and transporting the ores without dividing the furnace itself, and thus transform the working of the furnace into a continuous one. By means of this arrangement it will be made possible to introduce a certain quantity of ores into the endor finishingchamber of the furnace by the aid of one of said devices, and by the aid of the second device finish the roasting not by transporting the ores, but by simply stirring them. During the time the iinish-roasting is accomplished by the aid of the second device the first device is at rest. An objection raised to the effect, that the same result might be obtained by the aid of a single device, when the rabble or stirrer were made reversible in order to produce in the one instance a transporting motion and in the other instance a stirring motion of the ore, can be refuted by stating that by this method 0f working the whole body of ores contained in the furnace must be kept in motion, with the result that the ore would reach the endor finishing-part of the furnace in an almost completely roasted Specification of Letters Patent.

Patented March 24, 1908.

Serial No. 392,363.

condition, where for want of a too small percentage of sulfur an insuflicient degree of heat for the finish-roasting could be developed.

In the accompanying drawing t-Figure 1 is a cross-sectional view of the tubular shaft and sleeve, showing the attachment of the lower set of rabble-arms. Fig. 2 is a vertical sectional view of the improved mechanical roasting-furnace.

In the center of the annular furnace-walls 1 the foundation-block 2 is arranged and topped by the step-bearing 3 wherein the step 4 of the tubular shaft 5 rotates. On the arched furnace-top 6 there is arranged a hood 7 into which the products of combustion enter and are then conducted to any desirable point by the chimney-pipe 8. In the top of said hood a bearing 9 for the upper end of the tubular shaft 5 is arranged which carries a bevel-wheel 1() driven by the pinion 1 1. The pinion-shaft 12 receives its motion by means of the fast pulley 13 from a reversible motoror line-shaft (not shown) and may be set at rest when the driving-belt (likewise not shown) is shifted onto the loose pulley 14. The shaft 12 is journaled in the brackets 15 and 16. On the arched furnace-top there is likewise arranged the feed-hopper 17, into which the furnace-charge is thrown, and which can be opened and closed by means of the slide 18.

The furnace itself contains the top-floor 19 and the bottom-hoor 20 of which the latter may be heated, if necessary, by the aid of the gas heating-fines 21, into which the heating gases may be led in any known manner. Above the top-floor 19 the rabbles or stirrers 22 are arranged and connected with the tubular shaft 5 by inserting the tapered ends of their arms into the openings 23 of said shaft and let their noses 24 enter behind the ribs 25 which form an integral part of the division-wall 26.

Tothe lower end of the tubular shaft 5 is secured a collar 27 whose top-face contains a race for the anti-friction balls 2S provided for the support of the sleeve 29 which surrounds the tubular shaft 5 and holds and rotates the rabbles 30. The tapered ends of the rabble-arms enter into the openings 31 of the sleeve 29 and their noses 32 enter behind the ribs 33, as shown in Fig. 2. The sleeve 29 receives its motion from the pinion-shaft 34 by means of the pinion 35 and the bevelwheel 36, which shaft is provided with a fast pulley 37 and a loose pulley 38, and may, ike the shaft 12, be rotated in opposite directions by reversing the driving niotoror lineshaft (not shown) accordingly, or set at rest by placing the belt (likewise not shown) on the pulley 38.

The operation of the furnace is as follows: The ore to be roasted is introduced through the feed-hopper 17 into the upper chamber 39 of the furnace, the slide 18 closed and the rabbles 32 rotated in a direction so that the roof-shaped faces of the rabble-blades 40 face the ore and thus gradually spread lthe latter out over the floor 19. The necessary heat for igniting the sulfur of the ore is received from the lower chamber 41, wherein the roasting of the ore of a previous foreroasting is finished, if necessary by heating the bottom-floor 20 as indicated above. The heat ascends principally through the openings 42 in the floor 19 and to a small extent through the annular opening 43. After the desired degree of roasting has been attained the direction of rotation of the rabbles 22 is reversed as soon as the finish-roasted ore has been removed from the bottom-Hoor 20 and pushed by the oblique faces of the rabbleblades 44 through the discharge-door 45 by rotating the rabbles 3() in the direction of the arrow II of Fig. 1. The discharge-door is held in `its open position by means of the weighted angular catch 46. During the rotation of the rabbles 22 in this reverse direction the ore is pushed. towards the annular discharge-opening 43 in the floor 19 and prevented by the guard-ring 47 on the shaft 5 from entering between the latter and the sleeve 29.4 After the ore from the floor 19 has been thrown on the bottom-floor 2() the rabbles 22 are set at rest and the rabbles 3() rotated in the direction of the arrow I until the `roasting has been accomplished, vwhereupon the direction of motion of the rabbles 30 is reversed again `and the ore pushed through the discharge-door 45 in the manner described above. By means of this arrangement it is therefore made possible to stir and roast the ore which rests upon the bottomfloor until finished, while any ore on the topfloor 19 may be kept at rest by simply interrupting the rotation of the tubular shaft 5.

1t is evident that my invention is also applicable to a roasting-furnace with only one roasting surface, as `to make it such itwould only be necessary to give the Yupper set of rabbles a bent shape to let their blades rotate and sweep an annular Zone encircling the circular space swept by the lower set of rabbles.

I claim 1. A mechanical roasting-furnace provided with a plurality of sets of rabbles, means for operating and for setting at rest one setof rabbles, and means for operating and for setting at rest another set of rabbles irdependently of the first-named set of rabb es.

2. A mechanical roasting'- furnace, provided with a plurality of sets of rabbles arranged to work in different roasting-surfaces, a rotatable tubular shaft for sustaining one set of rabbles, means for rotating and for stopping said tubular shaft, a rotatable sleeve for sustaining another set of rabbles, and means for rotating and for stopping said sleeve independently of said tubular shaft sustaining said rst-named set of rabbles.

3. A mechanical roasting -furnace provided with a plurality of sets of rabbles arranged in different planes and working on different roasting-surfaces of said furnace, a rotatable tubular shaft detachably supporting one set of said rabbles, means for rotating said tubular shaft in opposite directions and for setting it at rest, a sleeve for detachably supporting another set of said rabbles,

`means for rotating said sleeve in opposite directions and for setting it at rest independently of said tubular shaft supporting the first-named set of rabbles.

4. In combination, a multi chambered mechanical roasting-furnace, a central tubular shaft, rabbles working in one of said furnace-chambers and detachably connected with said tubular shaft, means for reversibly driving and for setting said tubular shaft at rest, a sleeve revolubly mounted on said tubular shaft, rabbles working in another furnace-chamber and. detachably carried by said sleeve and means for reversibly driving and for setting said sleeve at rest independently of said tubular shaft carrying the firstnamed set of rabbles.

In testimony whereof l have signed my name to this specification in the'presence of two subscribing witnesses.

Witnesses T. GRAU, A. LEwEY. 

